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<h3 class="section" id="Conditional-Syntax-1"><span>4.2 Conditional Syntax<a class="copiable-link" href="#Conditional-Syntax-1"> &para;</a></span></h3>

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<p>A conditional in the C preprocessor begins with a <em class="dfn">conditional
directive</em>: &lsquo;<samp class="samp">#if</samp>&rsquo;, &lsquo;<samp class="samp">#ifdef</samp>&rsquo; or &lsquo;<samp class="samp">#ifndef</samp>&rsquo;.
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<li><a href="Ifdef.html" accesskey="1">Ifdef</a></li>
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